these might be used in combination with some simple IR or just cameras (need more CPU but could double as optical flow sensors) used to locate becaons for landing or grabbing things

Ideally, both sensors should have an unobstructed front view on pitch dimension, with aditional unobstructed jaw dimension for LIDAR.
Both sensors need to be able to independantly rotate on pitch axis for compensation of the angle of the drone when flying, and for scanning up and down (going in through windows, looking down when landing, etc) maybe rangefinder should also rotate on jaw axis on some fast servos for looking around independant of the drone orientation. not sure yet.

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IR and ultrasound were also options, they are cheap but tricky and unreliable, (ultrasound behaves extra badly due to propeller noise on drones)
These things can be compensated for, but laser rangefinding will always afaik give more accuracy and reliability at a price.